Bioresorbable polymeric clayey and sticky substance

Abstract

This invention provides a claycy and sticky substance as a new biomaterial that cannot be found in the current medical field, which is bioresorbable, shows tackiness, plasticity and shape holding ability at a temperature of approximately from 30 to 40° C. and can give unrestricted shapes at body temperature or more by increasing its fluidity. This clayey and sticky substance comprises a copolymer of two or more bioresorbable monomers, preferably any one of copolymers of p-dioxanone with D-lactic acid, L-lactic acid, D,L-lactic acid, trimethylene carbonate and ε-caprolactone, or a mixture of two or more of these copolymers. This clayey and sticky or clayey substance is suited for a hemostatic material, an adhesive material for tissues, a prosthetic material for tissue reconstruction use, a carrier of drug delivery system, a plugging material, an accretion-preventing material and a scaffold material for tissue engineering use.

What is claimed is:  
     
       1. A bioresorbable polymeric clayey and sticky substance which comprises at least one copolymer selected from the group consisting of a copolymer of p-dioxanone with D-lactide, which has a weight average molecular weight of from 2,000 to 40,000, a copolymer of p-dioxanone with L-lactide, which has a weight average molecular weight of from 2,000 to 40,000 and a copolymer of p-dioxanone with D, L-lactide, which has a weight average molecular weight of from 3,000 to 50,000, wherein the ratio of p-dioxanone occupying the copolymer is from 50 to 95 mol %, and 
       wherein said substance shows tackiness, plasticity and shape holding ability at a temperature of approximately from 30 to 40° C. and can increase its fluidity to give an optional shape at 40° C. or higher.  
     
     
       2. A bioresorbable polymeric clayey and sticky substance comprising a star-shaped copolymer comprised of a core of a multifunctional alcohol and one of the copolymers as defined in  claim 1  as segment chains substituted on the multifunctional alcohol. 
     
     
       3. The bioresorbable polymeric clayey and sticky substance according to  claim 2 , wherein said multifunctional alcohol is at least one member selected from the group consisting of glycerol, polyglycerol, and pentaerythritol. 
     
     
       4. The bioresorbable polymeric clayey and sticky substance according to  claim 1 , wherein adhesion of the copolymer measured at 37° C. by the 90° peeling test of JIS Z 0237-1991 is from 30 to 1,500 g (½ inch in width). 
     
     
       5. The bioresorbable polymeric clayey and sticky substance according to  claim 1 , which further comprises a poly-p-dioxanone having a weight average molecular weight which is larger than that of said copolymer. 
     
     
       6. The bioresorbable polymeric clayey and sticky substance according to  claim 1 , which has bubbles. 
     
     
       7. A hemostatic material, which comprises any one of the bioresorbable polymeric clayey and sticky substances of claims  1 - 6  and which further comprises at least one member selected from the group consisting of blood coagulation factors, drugs, cellulose oxide fibers, gelatin sponge and micro-fibrous collagen. 
     
     
       8. An adhesive material or clayey material for tissues, which comprises any one of the bioresorbable polymeric clayey and sticky substances of claims  1 - 6  and which further comprises at least one member selected from the group consisting of active ceramics powder, cytokine, derivatives of chitin or chitosan, hyaluronic acid, drugs, and other bioresorbable polymers. 
     
     
       9. The adhesive material according to  claim 8 , wherein the adhesion of said material measured at 37° C. by the 90° peeling test of JIS Z 0237-1991 is from 100 to 1,300 g (½ inch in width). 
     
     
       10. A prosthetic material for tissue reconstruction use, which comprises any one of the bioresorbable polymeric clayey and sticky substances of claims  1 - 6  and which further comprises at least one member selected from the group consisting of bioactive ceramics powder, cytokine, derivatives of chitin or chitosan, hyaluronic acid, drugs, bone fragments, cartilage fragments, and other bioresorbable polymers. 
     
     
       11. A carrier for drug delivery system use, which comprises any one of the bioresorbable polymeric clayey and sticky substances of claims  1 - 6  and which further comprises at least one member selected from the group consisting of synthetic or natural drugs, hormones, cytokine and enzymes. 
     
     
       12. A bioresorbable polymeric clayey and sticky substance which comprises at least one copolymer selected from the group consisting of a copolymer of p-dioxanone with D-lactide, which has a weight average molecular weight of from 2,000 to 40,000, a copolymer of dioxanone with L-lactide, which has a weight average molecular weight from 2,000 to 40,000 and a copolymer of p-dioxanone with D,L-lactide, which has a weight average molecular weight of from 3,000 to 50,000, wherein the ratio of p-dioxanone occupying the copolymer is from 50 to 95 mol %, and wherein said substance has not or slight tackiness at a temperature of lower then 30° C., but has tackiness, plasticity and shape holding ability at a temperature of approximately from 30 to 40° C. and can increase its fluidity to give an optional shape at 40° C. or higher.